It is a special remoted cable for Canon EOS series, it control the flash simultaneously by connecting Canon camera and the external flashgun, the function as well which set on the top of the camera. Support all functions of Canon EOS, as well all E-TTL functions of Canon flash system.
Move your E-TTL Flash off-camera to get any lighting angle you desire, and still retain all the functions and capabilities possible with Canon E-TTL ("Intelligent Through-The-Lens") Flash Photography.
The function for this shoe cord is very similar to Canon OC-E3, and it is 100% Compatible with Canon OC-E3 Off Camera Shoe Cord.
Off camera TTL shoe cord
Maintains all on-camera flash functions (including E-TTL II) for one Canon
Compatible shoe-mount flash unit used off-camera at distances up to 5 feet
Compatible with all Canon EOS or G series cameras, digital or film, except for the 630 and RT cameras
Cable has a 5 feet heavy-duty coiled cord and features a shoe mount on the bottom of the flash connection shoe, as well as a 1/4-inch, 20 sockets.
Any Canon SLR (Digital or Film) and Flash combination can make use of this Off-Camera cord.
It is fully compatible with the 220EX, 300EZ, 380EX, 420EZ, 420EX, 430EZ, 430EX, 480EG, 540EZ, 550EX, 580EX II
1 x OC-E3 TTL Remote Cord
1 x English manual